1. Field of the Invention
The present invention relates to a therapy or prophylaxis of Klebsiella pneumoniae infections, particularly to a therapy or prophylaxis of K. pneumoniae infections with a newly isolated lytic bacteriophage specifically against the K. pneumoniae. 
2. Description of the Related Art
Klebsiella pneumoniae, belonging to the family of Enterobacteriaceae and the genus of Klebsiella, is a gram-negative bacterium widely found in the normal flora of the intestinal and respiratory tracts of humans. However, the K. pneumoniae is also a significant opportunistic pathogen, usually causing severe diseases such as pneumonia in immunocompromised individuals, children or nosocomial patients. In clinical medicine, K. pneumoniae infections are primary characteristics of liver necrosis, urinary inflammation and septicemia. Once the patients have been diagnosed, a proper treatment must be given straightaway to avoid the serious complications and high mortality risks of K. pneumoniae infections.
Traditionally, the treatment of K. pneumoniae infections is mainly based on antibiotics, such as aminoglycosides (including gentamicin, tobramycin and amikacin) and cephalosporins. Nevertheless, due to occurrences of multiple drug-resistant strains currently, the therapy of K. pneumoniae infections has become both more difficult and essential. On the other hand, an increasing amount of K. pneumoniae infected patients in Taiwan have developed serious complications such as pyogenic liver abscess, metastatic meningitis and endophthalmitis, particular to diabetes mellitus and chronic respiratory cases. In these situations, around a 10˜30% rate of mortality has been experienced, and serious sequelae may arise, even if the patient is given proper antibiotic treatment.
As reported by recent researches, several genetic loci of the K. pneumoniae have been identified as virulence genes, and it is suggested that virulence factors encoded from the virulence genes show strong resistance to human immune system, being significantly invasive during infection. As a result, conventional therapy and prophylaxis may be ineffective in relieving K. pneumoniae infections in Taiwan.
Bacteriophages, also known as phages, are viruses that infect bacteria. These viruses may rapidly attach, penetrate and immediately reproduce in the target bacteria followed by lyse and release from the bacterial cell, which can be an alternative therapeutic strategy for K. pneumoniae infections. It has been reported that the bacteriophage treatment is sufficient to suppress the infections of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa in some western countries. Through the bacteriophage treatment, the therapy of bacterial infections can be achieved more economically and effectively, with no risk of drug-resistance or safety issues. Thus, regarding the severity of K. pneumoniae infections and its complications in Taiwan, there is an urgent need of providing a new therapy or prophylaxis of K. pneumoniae infections with a lytic bacteriophage specifically against the invasive K. pneumoniae in Taiwan.